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Edexcel - Chemistry Unit 2 - 4 June 2013 Watch

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    whats the shape and bond angles of: C2H6, C2H4, CH3OH AND CH3Cl thanks
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    (Original post by Jayqwe)
    What about Fluorine?
    Fluorine is an exception always. "The atom is so small that the repulsion between the in-coming electron and the seven electrons in the second shell reduces the energy liberated by the attraction between the incoming electron and the nucleus"

    That's what george facer says, but I didn't quite understand it myself (if you do then I'd be grateful if you could explain it ). However I would no worry about this and stick with Cl, Br & I. Fluorine as a reducing or oxidizing agent is not mentioned in any other book & in past papers.
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    (Original post by SophieL1996)
    whats the shape and bond angles of: C2H6, C2H4, CH3OH AND CH3Cl thanks
    C2H6 - tetrahedral 109.5
    C2H4 - trigonal planar 120
    (though to be fair it's 118,121,121.. but I think they'll accept 120 )
    CH3OH - tetrahedral 109.5, bent 104.5
    CH3Cl - tetrahedral 109.5
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    (Original post by posthumus)
    Fluorine is an exception always. "The atom is so small that the repulsion between the in-coming electron and the seven electrons in the second shell reduces the energy liberated by the attraction between the incoming electron and the nucleus"

    That's what george facer says, but I didn't quite understand it myself (if you do then I'd be grateful if you could explain it ). However I would no worry about this and stick with Cl, Br & I. Fluorine as a reducing or oxidizing agent is not mentioned in any other book & in past papers.
    You mean Chlorine is the most powerful oxidizing agent of the halogens?
    But all of Google says that fluorine can oxidize even chlorine and water?
    :confused:
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    (Original post by StUdEnTIGCSE)
    You mean Chlorine is the most powerful oxidizing agent of the halogens?
    But all of Google says that fluorine can oxidize even chlorine and water?
    :confused:
    Well it's left out of book for a reason I guess I've seen in previous papers that Chlorine is accepted to be the most powerful oxidizing agent. So I would honestly just stick with Chlorine.
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    (Original post by posthumus)
    C2H6 - tetrahedral 109.5
    C2H4 - trigonal planar 120
    (though to be fair it's 118,121,121.. but I think they'll accept 120 )
    CH3OH - tetrahedral 109.5, bent 104.5
    CH3Cl - tetrahedral 109.5
    thank you why is c2h2 trigonal planar though?
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    are we all ready to get raped by edexcel tomorrow hahahahahah

    anywayz every just listen to this

    https://www.youtube.com/watch?v=HgzGwKwLmgM
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    (Original post by SophieL1996)
    thank you why is c2h2 trigonal planar though?
    C2H4 is trigonal planar because if you cut it in half it has CH2 and a double bond which resembles the shape of a triangle and if you do 360/3 you get 120
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    (Original post by SophieL1996)
    thank you why is c2h2 trigonal planar though?
    There's 3 bonds around the carbon atom

    2 single bonds (C-H) & 1 double bond (C=C) & there's no lone pairs
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    What do we need to know about fullerenes ?
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    Can someone confirm this...

    When we are titrating  K_2MnO_4 it is kept in the burette.
    And in iodometric tritrations iodine is in the conical flask and at the end point the starch complex turns from blueblack to colourless?
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    (Original post by StUdEnTIGCSE)
    Can someone confirm this...

    When we are titrating  K_2MnO_4 it is kept in the burette.
    And in iodometric tritrations iodine is in the conical flask and at the end point the starch complex turns from blueblack to colourless?
    Yeah, that's right
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    Am I right to believe the mark scheme makes no sense over here ? & is not answering the question

    Name:  CHM2WTFMS.png
Views: 100
Size:  48.9 KB

    Could someone also explain to me how to do this question :

    When chlorine is added to a solution containing bromide or iodide ions, a colour
    change occurs. What solvent would you add to the mixture to confirm the
    identity of the halogen produced?


    Thanks in advance !
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    (Original post by TheUndercoverPanda)
    What do we need to know about fullerenes ?
    Everything
    Just a few uses like they can cage drugs, etc...
    And their electrical conductivity and general properties...


    Posted from the TSR iPad app
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    (Original post by posthumus)
    Am I right to believe the mark scheme makes no sense over here ? & is not answering the question

    Name:  CHM2WTFMS.png
Views: 100
Size:  48.9 KB

    Could someone also explain to me how to do this question :

    When chlorine is added to a solution containing bromide or iodide ions, a colour
    change occurs. What solvent would you add to the mixture to confirm the
    identity of the halogen produced?


    Thanks in advance !
    Add a hydrocarbon solvent like hexane and it turns purple


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    what is the name of (ch3)2 chch3oh ? what does it look like?
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    tdoes anyone know what back titrations are? do we need to know about them, my teacher says yes but ive never come across this term before..
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    (Original post by SophieL1996)
    what is the name of (ch3)2 chch3oh ? what does it look like?


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    Surely you must be able to name this?
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    Can anyone explain how this question is done please... Couldn't find stuff about it in the textbook or CGP revision guide...
    It's from the January 2012 paper btw
    Name:  ImageUploadedByStudent Room1370261832.240696.jpg
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    thanks
 
 
 
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